There was a fall of red snow in southwestern Europe as a result of a cold trough that penetrated from the north towards the central Mediterranean and Saharan Africa, together with movement eastwards. A strong southwesterly flow formed along the eastern flank of the trough. This flow transported a large amount of red Saharan dust, which mixed with the snowfall in the area and painted the snow red.

中文翻译：

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东欧出现红色积雪。案例研究

由于西北向北部向中部地中海和撒哈拉以南地区渗透，随着寒冷的低谷，欧洲西南部出现了红色的大雪。沿槽东侧形成强烈的西南风。这股水流运送了大量撒哈拉沙漠红色的尘埃，这些尘埃与该地区的降雪混合并漆成红色。